Heat motor operated valve



Feb. 9, 19 635 R. A. WHITLOCK HEAT MOTOR OPERATED VALVE Filed May 16, 1962 MOTION TEMPERATURE @mwv ew States Bibflflflh Patented Feb. 9, 1965 3,169,008 IEAT MOTOR OPERATED VALVE Robert A. Whitlock, Rockford, Ill, assignor to Alqlil amatic Ind, Rockford, Ht, a corporation of Filed May 16, 1962, Ser. No. 195,181 7 Claims. (Cl. 25111) This invention relates to valves and particularly to a heat motor operated valve.

Various important objects of this invention are to provide a heat motor operated valve which produces large forces for opening and closing the valve to achieve positive and reliable operation; which produces a large valve movement for full and restricted flow through the valve and to avoid collection of foreign material around the valve seat; and which is simple in construction and economical to manufacture.

Another object of this invention is to provide a heat motor operated valve having an improved arrangement for controlling the temperature of the heat motor to prevent overheating of the heat motor Without requiring auxiliary controls for de-energizing the heat motor when the valve is actuated.

A more particular object of this invention is to provide a heat motor operated valve in which the heat motor is mounted on the valve body to be cooled thereby and which is so arranged as to prevent spurious cycling of the valve due to the sudden cooling action of the liquid which flows through the valve upon opening of the same.

These, together with other objects and advantages of this invention will be appreciated as the same becomes better understood by reference to the following detailed description when taken in connection with the accompanying drawings wherein:

FIG. 1 is a diagrammatic view illustrating the heat motor operated valve employed as a drain valve in a control system for a water treatment apparatus;

. FIG. 2 is a fragmentary sectional view through the valveillustrating the same in its closed position;

FIG. 3 is a sectional view through the valve illustrating the same in its open position; and

FIG. 4 is a graph indicating the motion-temperature relation in the heat motor.

While the heat motor operated valve of the present invention is generally adapted for controlling the flows of liquids, it is particularly designed for use as a drain valve for a control system of a Water treatment apparatus, and is illustrated applied to such a system in FIG. 1. In general, the water treatment apparatus includes a treatment tank 11 having top and bottom tank connecting conduits 12 and 13, and a main control valve 14 for reversibly controlling the flows of fluid through the treatment tank. The valve includes an inlet chamber 15 and top and bottom ports 16 and 17 and a valve member 18 movable from a position closing the lower port 17 to a position closing the upper port 16. When the valve member is in its lower position, raw water passes from the inlet chamber 15 through the upper chamber 19 and outlet 21 to the upper conduit 12. Treatedwater from the lower end of the tank passes through the loWer conduit 13 into the passage 22 in the valve and past a check valve 23 to a service outlet 24. A drain passage 25 communicates with the upper chamber 19 and a means such as the plunger 26 is connected to the valve member 18 to raise the valve member when the drain valve is open, to thereby reverse the flow through the treatment tank. When the valve member is in its raised position, raw water flows from the inlet chamber 15 through the lower chamber 28 and ejector 29 to the bottom of the tank and the etfluent from the top of the tank flows through the upper chamber 19 to the drain 25. The heat motor operated valve 10 is provided in the drain line 30 to control the flow of fluid therethrough. The heat motor is conveniently automatically operated as under the control of a timer 31.

Referring now more specifically to the heat motor operated valve 10 illustrated in FIGS. 2 and 3, the heat motor valve includes a valve casing having a body 33 and a cap 34 attached to one end of the body. The cap is conveniently threadedly attached to the body and is sealed thereto as by an O-ring 35. The body has a flow chamber 37 extending therethrough and has an outlet passage 38 communicating therewith intermediate the ends of the flow chamber. The inlet end of the valve body is counterbored at 41 and provides a valve seat 42 around the flow chamber 37. The other end of the valve body is shaped for forming a seat for the heat motor capsule and, advantageously, the end of the valve body is counterbored at 43 to receive the end of the heat motor capsule to be described hereinafter. An inlet opening 44 is formed in the cap 34 and is adapted for connection to the drain pipe 30 and a valve member 45 is provided for controlling flow through the port 42 to the drain passage 38. As shown, the valve member includes a stem 46 having a socket 47 at one end and a reduced diameter extension 48 at the other end and which receives a valve element 49 carrying a gasket 51. A compression spring 52, conveniently of conical configuration, is interposed between the cap 34 and the valve member 45 to yieldably urge the valve member to its closed position shown in FIG. 2.

The heat motor capsule includes a generally annular shell 53 which is closed at one end by an end wall 54- and which has an outwardly extending peripheral flange 55 at its other end. A plunger guide member, conveniently in the form of a disk 56, overlies the flanged end of the shell and is atfixed to the shell as by having the rim 57 rolled or crimped over the periphery of the guidemember. A thermally expansible material, preferably of the type which changes to a state when heated to a preselected operating temperature, for example, from a solid to a liquid state, is disposed within the shell 53. A plunger 63 is slidably mounted in a bore 64 in the guide member and has the inner end thereof extending into the shell. A resilient body 65 is disposed in the shell between the thermally expansible material 61 and the plunger 63 to apply the pressure from the thermally expansible material to the plunger. The other end of the plunger 63 extends into the socket 47 in the valve stem. The plunger is conveniently slidably received in the socket in the valve stem and engages and moves the stem after an initial relatively small lost motion, as is clearly shown in FIGS. 2 and 3.

Heat motors are relatively slow acting due to the time delay in bringing the expansible material up to temperature to operate the plunger 64, and the time delay in cooling the expansible material to allow retraction of the plunger. In order to improve the speed of response in opening the valve, it is necessary to heat the capsule at a rate somewhat in excess of the minimum rate which would be required over a long period to raise the capsule temperature to the proper operating level. Similarly, in order to improve the speed at which the valve will close, it is also preferable to cool the heat motor at a rate somewhat greater than the rate at which the heat motor would cool in ambient air. In order to prevent overheating of the valve and to also improve the speed at which the valve will close, the heat motor is mounted in a manner to be cooled by the main valve body and the liquid flowing therethrough. Difliculties, however, were encountered due to the tendency of the heat motor and valve to cycle or hunt. As the heat motor opens the valve, the liquid flow through the valve commences with a corresponding increase in the cooling action on the valve. In accordance with the present invention, an improved mounting for the heat motor is provided which provides a controlled cooling of the heat motor and avoids cycling of the heat motor and valve. For this purpose, a heat insulating disk 71, advantageously formed of a gasket material such as rubber or the like, is disposed between the guide member 56 and the seat on the end of the valve body to thermally insulate the capsule from direct contact with the liquid in the fiow passage 37 and to also thermally insulate the capsule from direct metal-to-metal contact with the valve body. In addition, the disk 71 also functions to seal the interface between the capsule and the valve body to prevent the leakage of fluid thereby. A further ring 72 of insulating material is interposed between the periphery of the capsule and the walls of the counterbore 43 to prevent direct metal-to-metal contact therebetween. A heat conducting metal clamp ring 75 is mounted as by threading on the end of the valve body and has a flange portion rs overlying the flange portion 55 of the shell to clamp the capsule to the valve body and to also provide a metal-tometal heat conduction path between the shell and the body. The valve body is also peripherally grooved at 78 closely adjacent the capsule seat, to form a thin walled portion 79 around the flow chamber 37 and a thin generally radially extending flange portion 80 underlying the heat motor and forming the seat therefor. As will be noted, the ring 75, flange portion 81 and thin walled portion 79 form a controlled heat conduction path that extends from the shell through the flanged ring 75, the capsule seat and thin walled portion 79 to the main body of the valve. The latter is cooled by the liquid flowing through the valve and thus functions to limit the temperature rise of the heat motor during actuation of the same without requiring auxiliary controls for de-energizing the heat motor. The thermally expansible material in the shell is heated as by heating element 81 conveniently encased in a ceramic shell 82. The heating element is connected as by conductors 83 to a source'of power (not shown) under the control of the timer 31. The heater extends around the shell and maintained in heat conducting relation therewith as by a split heat conducting metal sleeve 34. The heating element is thermally insulated from the clamp ring 75 as by an insulating disk 86 to prevent heating of the clamp ring during energization of the heating element and is encased in a casing 91 conveniently detachably mounted on the ring 75.

When a heat motor is heated, the expansible material begins to expand at a temperaturesuch as shown at t1 in FIG. 4 and the material continues to expand and move the plunger at a relatively rapid rate until the heat motor reaches a temperature such as t2 when the change of state of the expansible material is substantially completed. Further heating of the heat motor produces a relatively small additional motion. However, if the heat motor capsule is heated above a preselected temperature such as indicated at t4, permanent distortion or damage to the capsule will occur. Heating element 81 is selected to have a heating capacity somewhat greater than necessary to heat the capsule to an operating temperature range above the knee in the curve of FIG. 4 and below the temperature t4 at which permanent damage will occur. Such a range is indicated between t2 and t3 in FIG. 4. Thus, in the absence of the aforedescribed cooling arrangement, as the heating element is energized, the temperature of the capsule will tend to continue to rise. However, the aforementioned clamp ring 75 and thin walled portion 79 of the valve body provide a controlled heat conduction path which limits the temperature rise of the heat motor to a level in the range t2-t3 which is below that at which permanent deformation or damage to the heat motor will occur. i

The rate of heat conduction from the shell to the body will increase as the temperature of the capsule increases a relative to the body, and the aforedescribed heat conduction path is proportioned and correlated with the heat in- 4 put from the heating element so as to conduct heat from the capsule tothe body at a rate suflicient to maintain the temperature in the range t2t3. As will be noted, temperature changes in this range do not produce a large movement of the valve rnember. Because of the relatively long length of the heat conduction path, the capsule is not cooled suddenly by the initial flow of liquid as the valve begins to open and, accordingly, spurious reclosing of the valve after its initial opening is avoided. Further, since the valve movement is small for temperature changes in the range i243, there is little or no hunting or cycling of the valve, due to moderate changes in liquid temperature or rate of flow;

1. A valve comprising a heat conducting metal valve casing defining a flow chamber opening at one side of the casing, said casing having an inlet passage and an outlet passage communicating with said chamber and .a valve port intermediate said inlet and outlet passages,

a valve member for controlling flow through said port, spring means yieldably urging said valve member to one position, a heat motor capsule including a rigid annular heat conducting metal shell closed at one end and having a rigid plunger guide member closing its other end, a plunger slidably mounted in said guide member and engaging said valve member for moving the same, a thermally expansible material in the shell and a resilient member extending across said other end of the shell and engaging said plunger for transmitting pressure from the thermally expansible material to the plunger, 'means including an electrical heating element for heating the expansible material in the capsule, said capsule being disposed at said one side of said casing, with said guide member extending across said open end of said flowchamber, heat insulating means insulating said guide member from contact with the liquid in said chamber and insulating said shell from. direct metal-to-metal contact with said valve casing, and means including a heat con ducting metal ring engaging said shell and said valve casing for clamping the capsule to the casing and for providing a metal-to-metal heat conduction path between the shell and said casing for limiting the temperature rise in said shell.

2. A valve comprising a heat conducting metal valve casing defining a flow chamber opening at one side of the casing, said casing having an inlet passage and an outlet passage communicating with said chamber and a valve port intermediate said inlet and outlet passages, a valve member for controlling flow through said port,

spring means yieldably urging said valve member to one position, a heat motor capsule including a rigid annular heat conducting metal shell closed at one end and having a rigid plunger guide member closing its other end, a plunger slidably mounted in said guide member and engaging said valve member for moving the same,- a thermally expansible material in the shell and a resilient member extending across said other end of the shell and engaging said plunger for transmitting pressure from the thermally expansible material to the plunger, means including an electrical heating element for heating the expansible material in the capsule, said casing having a counterbore at said one side around said open end of said flow chamber, said capsule havingone end disposed in said counterbore with said guide member extending across said open end of said flow chamber, heat insulating means insulating said guide member from contact with the liquid in said flow-chamber and insulating said shell from direct metal-to-metal contact with the walls of said counterbore, and means including a heat conducting metal ring engaging said shell and said valve casing for clamping the capsule to the casing, and for providing a metal-to-metal heat conduction path between the shelland the valve casing.

3. A valve comprising a heat conducting metal valve casing defining a flow chamber having an opening at one side of the casing, said casing including an integral body having a seat portion at said one side of said body around the open end of said flow chamber, a main body portion, and a thin walled portion around said flow chamber connecting said seat portion to said main body portion, said thin walled portion having a substantially thinner wall section than said main body portion to provide a restricted heat conduction path between the main body portion and said seat portion, said valve casing having an inlet passage and an outlet passage communicating with said flow chamber and a valve port intermediate said inlet and outlet passages, a valve member for controlling fiow through said port, means yieldably urging said valve member to one position, a heat motor capsule including a rigid annular heat conducting metal shell closed at one end and having a rigid plunger guide member closing its other end, a plunger slidably mounted in said guide member and engaging said valve member for moving the same, a thermally expansible material in said shell and a resilient member extending across said other end of said shell and engaging said plunger for transmitting pressure from the thermally expansible material to the plunger, means including an electrical heating element for heating the expansible material, said capsule being mounted on said seat portion with said guide member extending across said open end of said flow chamber, heat insulating means insulating said guide member from contact with the liquid in said flow chamber and insulating said shell from direct metal-to metal contact with said valve casing, and means including a heat conducting metal ring engaging said shell and said seat portion of said valve casing for clamping the capsule to the seat portion, said ring member and said thin walled portion of the valve casing providing a controlled heat conduction path between the shell and the main body portion for preventing overheating of the shell.

4. A valve comprising a heat conducting metal valve casing defining a flow chamber having an opening at one side of the casing, said casing including an integral body having a seat portion at said one side of said body around the open end of said flow chamber, a main body portion, and a thin walled portion around said flow chamber connecting said seat portion to said main body portion, said thin walled portion having a substantially thinner wall section than said main body portion to provide a restricted heat conduction path between the main body portion and said seat portion, said valve casing having an inlet passage and an outlet passage communicating with said flow chamber and a valve port intermediate said inlet and outlet passages, a valve member for controlling flow through said port, means yieldably urging said valve member to one position, a heat motor capsule including a rigid annular heat conducting metal shell closed at one end and having a rigid plunger guide member closing its other end, a plunger slidably mounted in said guide member and engaging said valve member for moving the same, a thermally expansible material in said shell and a resilient member extending across said other end of said shell and engaging said plunger for transmitting pressure from the thermally expansible material to the plunger, means including an electrical heating element for heating the expansible material, said seat portion of said valve casing including a counterbore around said open end of said flow chamber, said capsule having one end disposed in said counterbore with said guide member extending across said open end of said flow chamber, heat insulating means insulating said guide member from contact with the liquid in said flow chamber and insulating said shell from direct metal-to-metal contact with said seat portion, and means including a heat conducting metal ring engaging said shell and said seat portion of said valve casing for clamping the capsule to the seat portion, said ring member and said thin walled portion of the valve casing providing a controlled heat conduction path between the shell and the main body portion for preventing over-heating of the shell.

5. The combination of claim 4 wherein said electrical heating element extends around the outside of said shell, and heat insulating means is disposed between the heating element and said ring member.

6. A valve comprising, a heat conducting metal valve body having a valve port at one side and a capsule seat at the other side and a flow chamber extending between said valve port and said capsule seat, said body having an inlet communicating with said valve port and an outlet communicating with said flow chamber intermediate said valve port and said capsule seat, a valve member for controlling flow through said port, means yieldably urging said valve member to a position closing said port, a heat motor capsule including a rigid annular heat conducting metal shell closed at one end and having a peripheral outwardly extending flange at the other end, a rigid plunger guide member attached to the flange on said shell and overlying said capsule seat, a plunger slidably mounted in said guide member and extending into said flow chamber into engagement with said valve member for moving the same, a thermally expansible material in said shell and a resilient member extending across said other end of the shell and engaging said plunger for transmitting pressure from the thermally expansible material to the plunger, means including an electrical heating element for heating the expansible material in the shell, means insulating said guide member from contact with the liquid in the chamber, a heat conducting metal ring member engaging said flange on said capsule and said casing for clamping the capsule thereto, said body having a relatively thinner walled portion around said flow chamber adjacent said seat and forming a part of a controlled heat conduction path between the shell and the main portion of the valve body for limiting the temperature rise of the capsule.

7. The combination of claim 6 including a cap attached to said valve body around said inlet passage and having an opening therein adapted for connection to a liquid supply pipe, said means yieldably urging said valve member to a closed position including a spring disposed between said cap and said valve member.

References Cited in the file of this patent UNITED STATES PATENTS 2,055,133 Newell Sept. 22, 1936 2,249,101 Wile July 15, 1941 2,378,760 Ferguson June 19, 1945 2,806,375 Wood Sept. 17, 1957 2,974,869 Hajny Mar. 14, 1961 

6. A VALVE COMPRISING, A HEAT CONDUCTING METAL VALVE BODY HAVING A VALVE PORT AT ONE SIDE AND A CAPSULE SEAT AT THE OTHER SIDE AND FLOW CHAMBER EXTENDING BETWEEN SAID VALVE PORT AND SAID CAPSULE SEAT, SAID BODY HAVING AN INLET COMMUNICATING WITH SAID VALVE PORT AND AN OUTLET COMMUNICATING WITH SAID FLOW CHAMBER INTERMEDIATE SAID VALVE PORT AND SAID CAPSULE SEAT, A VALVE MEMBER FOR CONTROLLING FLOW THROUGH SAID PORT, MEANS YIELDABLY URGING SAID VALVE MEMBER TO A POSITION CLOSING SAID PORT, A HEAT MOTOR CAPSULE INCLUDING A RIGID ANNULAR HEAT CONDUCTING METAL SHELL CLOSED AT ONE END AND HAVING A PERIPHERAL OUTWARDLY EXTENDING FLANGE AT THE OTHER END, A RIGID PLUNGER GUIDE MEMBER ATTACHED TO THE FLANGE ON SAID SHELL AND OVERLYING SAID CAPSULE SEAT, A PLUNGER SLIDABLY MOUNTED IN SAID GUIDE MEMBER AND EXTENDNG INTO SAID FLOW CHAMBER INTO ENGAGEMENT WITH SAID VALVE MEMBER FOR MOVING THE SAME, A THERMALLY EXPANSIBLE MATERIAL IN SAID SHELL AND A RESILIENT MEMBER EXTENDING ACROSS SAID OTHER END OF THE SHELL AND ENGAGING SAID PLUNGER FOR TRANSMITTING PRESSURE FROM THE THERMALLY EXPANSIBLE MATERIAL TO THE PLUNGER, MEANS INCLUDING AN ELECTRICAL HEATING ELEMENT FOR HEATING THE EXPANSIBLE MATERIAL IN THE SHELL, MEANS INSULATING SAID GUIDE MEMBER FROM CONTACT WITHE THE LIQUID IN THE CHAMBER, A HEAT CONDUCTING METAL RING MEMBER ENGAGING SAID FLANGE ON SAID CAPSULE AND SAID CASING MEMBER ENGAGING SAID FLANGE ON SAID CAPSULE BODY HAVING A RELATIVELY THINNER WALLED PORTION AROUND SAID FLOW CHAMBER ADJACENT SAID SEAT SAID FORMING A PART OF A CONTROLLED HEAT CONDUCTION PATH BETWEEN THE SHELL AND THE MAIN PORTION OF THE VALVE BODY FOR LIMITING THE TEMPERATURE RISE OF THE CAPSULE. 